1. Field of the Invention
The invention relates to a matrix pin print head of the hinged-clapper-armature construction with several pin systems, which comprise in each case a magnet yoke limb pair, an electromagnetic coil, a hinged clapper armature, and a print pin, where a higher pin system number determines an outer print head diameter as a nominal diameter, or where a lower pin system number is associated with a smaller print head diameter than the nominal diameter, and where an electromagnetic coil support, which is produced by sintering or by precision casting, forms a single-piece component together with a base plate and the magnet yoke limb pairs.
2. Brief Description of the Background of the Invention Including Prior Art
Such a matrix pin print head is known, for example, from the German Patent Application DE-A1-3,412,855 or from the U.S. Pat. No. 4,230,038. These conventional constructions exhibit U-shaped magnet yoke arm pairs. In this case, the yoke arms are of a rectangular cross-section. However, such a construction requires too large a space and surface area. The problem of position and mold errors occurs during the production. In case of sintered parts or, respectively, of precision casted parts, filling deficiencies occur in the production tool. Such filling deficiencies result in nonuniformities of the magnetic flux. The magnetic flux depends, among other things, on the density of the material employed. In addition, calibration problems of the workpiece are generated. All difficulties are even further increased when the number of the pin systems employed is increased. Thus, in case of 18-pin or 24-pin systems and systems with even more pins, where the nominal diameter remains the same, it is possible only with great difficulty to coordinate the armatures relative to their angle side to the respective magnet yoke limbs or, respectively to guide the armatures.